Field of the Invention
The present invention relates to tumor ablation. More particularly, the present invention relates to cold plasma ablation of cancerous tumors.
Background of the Related Art
Plasma is an ionized gas that is typically generated in high-temperature laboratory conditions. Recent progress in atmospheric plasmas has led to the creation of cold plasmas with ion temperature close to room temperature. Earlier studies demonstrated the non-aggressive nature of the cold plasma. After it was shown, albeit indirectly, that plasma can interact with organic materials without causing thermal/electric damage to the cell surface, several biological applications were examined. Low-temperature or cold plasmas have an increasing role to play in biomedical applications. The potential use in biomedical applications has driven the development of a variety of reliable and user-friendly plasma sources. There is still some controversy with respect to the mechanism of plasma-cell interaction. Some authors have expressed the opinion that ion species play the most important role in plasma-cell interactions by triggering intracellular biochemistry. Alternatively, others have suggested that neutral species play the primary role in some plasma-cell interaction pathways. Furthermore, the effects of various ion species may be highly selective; different species can have either “plasma killing” (such as O) or “plasma healing” (such as NO) effects. The role of other species, such as O3 and OH, are not yet clear.
Even less clear is the nature of the interaction between cold plasmas and cancer tissue. Only limited research into the utility of cold plasma for cancer therapy has been performed. For the most part, these in-vitro studies are limited to skin cells and simple cellular responses to the cold plasma treatment. In addition, preliminary reports on plasma's in-vivo antitumor effect are reported. Recent studies have delineated cold plasma's effects on both the cellular and sub-cellular levels. On the cellular level, plasma effects include detachment of cells from the extracellular matrix and decreased migration velocity of cells. On the sub-cellular level, cell surface integrin expression is reduced.